Audio equipment is normally includes a receiving function for receiving AM radio broadcasting and FM radio broadcasting. Among them, for example, some equipment supposed to be used indoors has a structure that a separated antenna for receiving AM/FM radio broadcasting can be installed.
Various antennas for receiving AM/FM radio broadcasting to be used for the above-mentioned audio equipment have been proposed. For example, as an antenna for receiving FM radio broadcasting, for example, a simplified antenna called as a feeder antenna or a wire antenna is well known. Moreover, as an antenna for receiving AM radio broadcasting, an antenna composed of a plastic or the like and a lead wire wound around the plastic or the like is known.
However, the FM simplified antenna mentioned above has a line portion, such as a feeder or a wire, of about 1–2 m in length.
Consequently, when such an FM simplified antenna is installed to be used in audio equipment, it in necessary to expand the line portion to arrange it. Hence, the FM simplified antenna mars the appearance of the room in which the antenna is installed.
Moreover, in a case where an AM antenna and an FM antenna are separately configured, their connection with equipment is troublesome, and the antennas are difficult to handle.
Accordingly, the following antenna has been proposed as an antenna for receiving AM/FM radio broadcasting. According to the disclosure, an AM antenna is formed by winding an antenna coil around a magnetic material rod made of a ferrite, for example, in the shape of a solenoid, and a loop antenna for FM is formed by winding an enamel wire in a shape of a quadrilateral. Then, the AM antenna is arranged in parallel with one side of the FM antenna, and the AM antenna and the FM antenna are formed to be one body by fixing the AM antenna to the FM antenna with a mold resin (Japanese Patent Application Publication (KOKAI) No. SHO 56-122204 (FIG. 3)).
However, because the AM/FM antenna disclosed in Japanese Patent Application Publication (KOKAI) No. SHO 56-122204 mentioned above needs to fix the AM antenna and the FM antenna with each other by means of the mold resin, a process for molding the AM antenna and the FM antenna is needed at the time of manufacturing the AM/FM antenna. Moreover, the mold resin is needed as an antenna material.
Consequently, the AM/FM antenna disclosed in Japanese Patent Application Publication (KOKAI) No. SHO 56-122204 (FIG. 3) is not good in manufacturing efficiency thereof, and entails large cost for realizing the antenna.
Accordingly, the present invention was made in view of the problems described above, and aims to provide an antenna apparatus composed of an AM antenna and an FM antenna united to be one body more efficiently in manufacturing cost or cost.